Bosque del Apache National Wildlife Refuge — long known for its birds — is seeing more elk; however, the numbers at the Valles Caldera National Preserve appear to be unchanged.
“Fifteen years ago they were very uncommon, and now they’re very common,” said John Vradenburg, a U.S. Fish and Wildlife Service biologist at the wildlife refuge south of Socorro.
Estimates of the Bosque del Apache’s elk population now range from 30 up to 100, he said.
While this phenomena is occurring in the wildlife refuge, elk numbers are “holding fairly steady” in the Valles Caldera, said Director of Science and Education Dr. Bob Parmenter.
“We hunt them … and of course there’s predatoration and nature causes – diseases,” he said.
Looking at the numbers given by the State Department of Game and Fish, there are 4,500 elk in the Jemez Mountains and about 2,500-3,000 of those are in the caldera. He said there is no data to suggest that the population is shrinking or increasing.
One thing the Caldera staff, along with the Game and Fish, is studying is the calf mortality rate, Parmenter said. He said there should be 40-50 calves for every 100 cow but what they are seeing is 25-30 calves for every 100 cow.
The study will continue for the third year this summer. Volunteers are welcomed to participate in the study, call the Caldera at 661-3333 for more information.
In the wildlife refuge, Vradenburg speculated the elk arrived by way of the Rio Grande corridor, a natural travel route for animals of all sorts.
“It’s the main corridor for anything from a hummingbird to an elk,” he said.
Vradenburg, his colleagues and scientists from the New Mexico Department of Game and Fish have begun capturing elk and attaching radio tracking collars to the animals so scientists can track and study the growing elk herds.
As of late last week, researchers had captured and collared 14 elk. Vradenburg said the projects hopes to expand that to 30.
Researchers shoot the elk with a tranquilizer dart, attach the collar and gather data on the animals’ health.
They’re trying out a new test for signs of chronic wasting disease, a fatal disease that afflicts deer and elk in parts of New Mexico, said state Game and Fish biologist Kerry Mower.
Elk have expanded from the mountains of New Mexico to other habitats, since most big predators have disappeared and elk can live on a variety of plants, he said.
Vradenburg said three distinct herds appear to have become established at Bosque del Apache — one in the north, one in the center and the third in the south. He said refuge visitors driving a southern bird-watching loop frequently see elk in recently cleared farm areas.
Mower said it’s especially important to monitor for chronic wasting disease on the refuge. The disease spreads especially well in herds living close to one another, which happens at places like Bosque del Apache where there’s abundant food and few threats.
Parmenter agreed, saying that the elk seemed to have colonized that area in the last five to 10 years.
NOTE: The Associated Press contributed to this story.